JP2752415B2 - Bail roller opening and closing mechanism of printer - Google Patents

Description

Detailed Description of the Invention [Table of Contents] Overview Industrial application field Conventional technology (FIGS. 17 and 18) Problems to be Solved by the Invention Means for Solving the Problems (FIG. 1) Action Embodiment (A) Description of the first embodiment (FIGS. 2 to 7) (b) Description of the second to eighth embodiments (FIGS. 8 to 14) (c) Ninth embodiment Description (FIGS. 15 and 16) (d) Description of Other Embodiments [Overview] A dedicated motor is provided for a bail roller opening / closing mechanism of a printer for automatically opening / closing a bail roller for holding a print medium on a platen. A platen, a print head that moves along the platen and performs printing, and a print head that moves along the platen without affecting the paper loading operation. A space motor for moving along the platen; In a printer having a Beirurora for pressing the print medium onto Ten,
A driving mechanism for opening and closing the bail roller by the driving force of the space motor, a disconnection mechanism for disconnecting power in the driving mechanism, and a power transmission when an overload is applied to the power transmission in the driving mechanism. And a torque limiter that cuts off.

[Industrial applications]

The present invention relates to a bail roller opening and closing mechanism of a printer for automatically opening and closing a bail roller for holding a print medium on a platen.

The printer is provided with a bail roller for pressing a continuous form, a cut sheet (single form), and the like on a platen in the vicinity of a print head so as to perform a good printing operation.

In recent years, with the automatic loading of paper, a mechanism for automatically opening and closing a bail roller has been provided, and a technique capable of automatically opening and closing with a simple mechanism is required.

[Conventional technology]

 FIG. 17 is an explanatory diagram of a printer.

In the apparatus shown in FIG. 17, an opening 3a of a cover 3 serving as a paper discharge port is provided above a platen 2, and a print head 1 is provided on the left side.

The print head 1 moves along the platen 2 to perform printing on a cut sheet (cut sheet) SP inserted from the guide 5a or a continuous sheet LP fed by the tractor 5b.

A bail roller 4 for holding the paper is provided between the cover 3 and the upper part of the print head 1.
Can be moved in the direction of the arrow in the figure, and the sheet heading in the direction of the arrow is directed in the direction and discharged from the opening 3a.

When the automatic opening / closing mechanism of the bail roller 4 is provided, the bail roller 4 is opened before the continuous paper LP or the cut sheet SP starts to be loaded, and the bail roller 4 is closed after the paper is loaded.

 FIG. 18 is an explanatory diagram of the prior art.

In FIG. 18, the bail roller 4 is opened and closed using the rotational movement of an LF (line feed; paper feed) motor.

That is, the gear 50a of the rotation shaft of the LF motor 50 is
1, transmitted to G2, and transmitted to the gears G4, G5 at the end of the bail arm 4b by a planetary gear G3 operated by a magnet.

Gears G4, G5 are provided with teeth only in part so that they are on opposite sides, and the teeth of either gear G4, G5 mesh with the teeth carved at the end of the bail arm 4b,
The bail arm 4b is rotated, and the support shaft 4a of the bail arm 4b
Open / close the bail roller 4 provided in the above.

In the example of the figure, the rotation of the LF motor 50 in the direction of the arrow causes the gear G5 to rotate.
As a result, the bail arm 4b rotates in the opening direction of the bail roller 4.

After that, when the planetary gear G3 is again operated by the magnet and transmits power, the gear G4 is now set to the bail arm 4b.
Is rotated in the closing direction of the bail roller 4.

Further, as another conventional technique, a motor for opening / closing the bail roller 4 is provided, and the rotational movement of this motor is transmitted to a cam via several gears, and the bail arm 4b is swung by the movement of the cam. The opening / closing of the bail roller 4 continuous with the bail arm 4b is performed.

[Problems to be solved by the invention]

However, when the LF motor is used as the drive source for the automatic opening and closing of the bail roller, the bail roller is opened and closed while the paper is being loaded by the LF motor. In this case, there is a problem that a line feed deviation of paper occurs.

In addition, when a dedicated motor is provided, there is a problem that the cost is increased accordingly.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a bail roller opening / closing mechanism of a printer which can perform an automatic opening / closing operation of a bail roller without affecting a sheet loading operation without providing a dedicated motor.

[Means for solving the problem]

 FIG. 1 is a diagram illustrating the principle of the present invention.

According to the present invention, as shown in FIG. 1, a platen 2 and a print head 1 that moves along the platen 2 to perform printing,
In a printer having a space motor 6 for moving the print head 1 along the platen 2 and a bail roller 4 for holding a print medium on the platen 2, the bail roller 4 is opened and closed by the driving force of the space motor 6. A drive mechanism 7 for driving, a disconnection mechanism 8 for disconnecting power in the drive mechanism 7, and a torque limiter for disconnecting the power transmission when the power transmission in the drive mechanism 7 is overloaded are provided. It is a thing.

[Action]

Since the printing by the print head 1 is not performed during the paper loading operation, operating the space motor 6 during that time does not affect the printing operation.

Therefore, the present invention enables the bail roller 4 to be automatically opened and closed without affecting the loading operation and the like and without providing a dedicated motor by driving the bail roller 4 using the space motor 6 as a drive source. .

Further, since the torque limiter is provided, it is possible to prevent the mechanism from being destroyed and the pressure imprint on the paper.

〔Example〕

(A) Description of the first embodiment FIG. 2 is a block diagram of the first embodiment of the present invention, FIG. 3 is a sectional view of the first embodiment of the present invention, and FIG. It is a whole figure of an Example.

FIG. 3B is a cross-sectional view of FIG.
FIG. 3 (C) is a cross-sectional view in the B direction of FIG. 3 (A).

A pulley 61a is provided on the shaft 60 of the space motor 6, and a timing belt 62 is stretched between the pulley 61a and the other pulley 61b, as shown in FIG.

The carriage 10 on which the print head 1 is mounted is connected to the timing belt 62, and the carriage 10 and the print head 1 are moved along the platen 2 along a pair of guides 10 and 11.

The shaft 60 of the space motor 6 is further supported by a bracket 70 by a bearing 63, and a bevel gear 64 is
Is provided.

The shaft 71a is rotated on the bracket 70, and FIG.
As shown in (B), a bevel gear 71 which engages with a bevel gear 64 is provided, and further connected thereto, a rotating arm (crank) 72 is provided.
Is provided.

The rotating arm 72 has a bail roller 4 at the tip and a fulcrum.
It is connected by a rod 73 to a bail arm 4b that rotates about 40.

The bracket 70 includes a clutch lever 81 that rotates around a fulcrum 81b, an electromagnetic magnet 80 that drives the clutch lever 81, a coil spring 82 that applies a restoring force to the clutch lever 81, and a bevel gear 71 with the clutch lever 81. A pressing member 83 for sliding movement is provided.

The tip 81a of the clutch lever 81 is formed obliquely in cross section as shown in FIG. 3C, and is urged downward by FIGS. 3A and 3C by the operation of the electromagnetic magnet 80. It is inserted between the bracket 70 and the pressing member 83, and the pressing member
By moving 83 to the right in FIG. 3C, the bevel gear 71 is shifted to the right in FIG. 3C to engage the bevel gear 64 of the space motor 6.

5 and 6 are explanatory diagrams of the operation of the first embodiment of the present invention, and FIG. 7 is a time chart of the first embodiment of the present invention.

In a normal state, as shown in FIG. 4, the magnet 80 is off, and the bevel gear 71 and the bevel gear 64 are not engaged.

Further, the space motor 6 is not rotating, and the bail roller 4 is in a closed state.

In this state, when the sheet is loaded, the magnet 80 is turned on and the bevel gear 71 is shifted by the clutch lever 81 as shown in FIG.
The bevel gear 71 meshes with the bevel gear 64.

At this time, the tip 81a of the clutch lever 81 shifts the bevel gear 71 via the pressing member 83 as shown in FIG. 3 (C).
Is shifted horizontally without being inclined.

Then, the space motor 6 rotates in the reverse direction for a certain time.

Accordingly, as shown in FIG. 5 (A), the reverse rotation of the space motor 6 causes the rotating arm 72 to rotate via the bevel gears 64 and 71, and the bail arm 4b to rotate via the rod 73, and the bail roller 4 is opened.

When the rotation of the space motor 6 is turned off and the magnet 80 is turned off, as shown in FIG. 5B, the engagement between the bevel gears 71 and 64 is released, and the bail roller 4 is kept open.

When the bail roller 4 is opened, the paper is loaded as shown in FIG.

When the loading of the paper is completed, the magnet 80 is turned on again as shown in FIG. 6, the bevel gears 71 and 64 are engaged by the clutch lever 81, and then the space motor 6 is rotated in the forward direction.

Accordingly, as shown in FIG. 6, the forward rotation of the space motor 6 causes the rotating arm 72 to rotate via the bevel gears 64 and 71,
The bail arm 4b is rotated via the rod 73, and the bail roller 4 is closed.

Then, as shown in FIG. 7, the positive rotation of the space motor 6 is turned off, the magnet 80 is turned off, and the bevel gear is turned off.
The meshing of the gears 64 and 71 is released, the state is returned to the state shown in FIG. 4, the open / close operation is completed, and printing is started.

During this time, the print head 1 is moved right and left along the platen 2 by the space motor 6, but it does not matter since the printing is not started.

Thereafter, the electromagnetic magnet 80 is not turned on, and the power of the space motor 6 is not transmitted to the drive mechanism 7 of the bail roller 4 but is turned off.
, The bail roller 4 does not open or close.

Thus, using the space motor 6 as a drive source,
Disconnection mechanism 8 for power transmission of drive mechanism 7 (magnet 80, etc.)
And the bail roller 4 can be opened / closed.

(B) Description of Second to Eighth Embodiments FIG. 8 is a block diagram of a second embodiment of the present invention.

In the figure, the same components as those shown in FIGS. 1 to 6 are denoted by the same symbols.

In this embodiment, a belt is used in comparison with the first embodiment in which the rotary arm 72 and the rod 73 are used to convert the rotary motion into the oscillating motion.

That is, instead of the rotating arm 72, a pulley 74a is provided on the shaft 71a of the bevel gear 71, a pulley 74b is provided on the shaft 40 of the bail arm 4b, and a belt 74c is provided between the pulleys 74a, 74b.

Other parts such as the connecting mechanism 8 by the magnet 80 and the bevel gear 71 of the driving mechanism 7 are not replaced with those of the first embodiment, and their operations are the same as those in FIG.

 FIG. 9 is a block diagram of a third embodiment of the present invention.

In the figure, the same components as those shown in FIGS. 1 to 6 are denoted by the same symbols.

In this embodiment, a gear is used to convert the rotational motion into the swing motion of the bail arm 4b.

That is, the gear 75a is attached to the shaft 71a of the bevel gear 71, and the bail arm
A gear 75g is provided on the shaft 40 of 4b, and transmission gears 75b to 75f are provided therebetween.
It is connected by.

 FIG. 10 is a block diagram of a fourth embodiment of the present invention.

In the figure, the same components as those shown in FIGS. 1 to 6 are denoted by the same symbols.

In this embodiment, a compound cam is used to convert the rotary motion into the swing motion of the bail arm 4b.

That is, the gear 76a is attached to the shaft 71a of the bevel gear 71, and the bail arm
A gear 76i is provided on the shaft 40 of 4b, and the power of the gear 76b is
It is transmitted to the cam 76d by 6c.

An L-shaped lever 76e is engaged with the cam 76d.
L-shaped lever 76e is rotated by 76d, and L-shaped lever 76
The rotation of e is transmitted to the gear 76i by the gears 76f to 76h to rotate the bail arm 4b.

 FIG. 11 is a block diagram of a fifth embodiment of the present invention.

In the figure, the same components as those shown in FIGS. 1 to 6 are denoted by the same symbols.

In this embodiment, the plate cam 77e is used to convert the rotational motion into the swing motion of the bail arm 4b.

That is, the gear 77a is provided on the shaft 71a of the bevel gear 71, and the gear 77
The plate cam 77e is rotated via b, 77c, and 77d.

An L-shaped lever 77f biased by a tension spring 77g is engaged with the plate cam 77e, and a gear 77h provided on the shaft of the L-shaped lever 77f is provided with a gear 77i provided on the shaft 40 of the bail arm 4b.
And are engaged.

Therefore, the bail arm 4b is turned in the arrow closing direction by turning the L-shaped lever 77f urged clockwise by the pulling bus 77g in the counterclockwise direction by the plate cam 77d.

 FIG. 12 is a block diagram of a sixth embodiment of the present invention.

In the figure, the same components as those shown in FIGS. 1 to 6 are denoted by the same symbols.

In this embodiment, an oscillating slider crank mechanism is used to convert the rotational motion into the oscillating motion of the bail arm 4b.

That is, a rotating plate (crank) 78a provided on the engaging pin 780 is provided on the shaft 71a of the bevel gear 71, and the slider 78b swinging about the fulcrum 782 is moved to the sliding hole 781 by the engaging pin 780.
And the front end is attached to the rear end of the bail arm 4b.

In this embodiment, the bail arm 4b is opened / closed by rotation of the space motor 6 in one direction.

 FIG. 13 is a block diagram of a seventh embodiment of the present invention.

In the figure, the same components as those shown in FIGS. 1 to 6 are denoted by the same symbols.

In this embodiment, a rack 78d and a pinion 78c are used to convert a rotational motion into a swing motion of the bail arm 4b.

That is, a pinion gear 78c is provided on a shaft 71a of the bevel gear 71, and a rack 78d having a tip engaged with the bail arm 4b.
Is provided.

 FIG. 14 is a block diagram of an eighth embodiment of the present invention.

In this embodiment, instead of using a bevel gear mechanism for transmitting power, a worm gear mechanism is used.

That is, a spur gear 79a slidable in the axial direction is provided on the shaft 60 of the space motor 6, and the clutch lever 83 of the disconnection mechanism 8 is configured to slide the spur gear 79a about the fulcrum 83a.

A worm gear 79b is provided on the spur gear 79a, a pulley 79c is provided coaxially on the worm gear 79b, and a shaft of the bail arm 4b is provided.
A pulley 79e provided at 40 is connected with a belt 79d.

In this example, the clutch lever 83 is driven by driving the magnet 80.
As a result, the spur gear 79a is shifted, and the meshing with the worm gear 79b is disconnected.

When the worm gear 79b and the spur gear 79a are engaged, the driving force of the space motor 6 is reduced by the pulley 79c and the belt 7
It is transmitted to the pulley 79e via 9d, and swings the bail arm 4b.

(C) Description of the Ninth Embodiment FIGS. 15 and 16 are block diagrams of a ninth embodiment of the present invention. FIG. 15 (A) is a side view, and FIG. 15 (B) is an exploded view thereof. FIGS. 16A and 16B are cross-sectional views.

In this embodiment, a torque limiter (power transmission limiting mechanism) is provided between a bevel gear 71 and a rotating arm (crank) 72 in addition to the configuration of the first embodiment.

That is, the convex portion 71b is provided on the bevel gear 71, and the concave portion 72b is provided on the crank 72 correspondingly.

The projection 71b of the bevel gear 71 has a large number (eight in the figure) of triangular projections around the circumference as shown in FIG.

On the other hand, a large number (seven in the figure) of projections 72a are provided in the concave portion 72b of the crank 2 as shown in FIG.

Then, as shown in FIG. 16 (A), a leaf spring 71c having a substantially U-shape and having a shape engaging with the triangular protrusion of the convex portion 71b of the bevel gear 71 is provided with a convex portion 71b of the bevel gear 71, It is inserted between the concave portions 72a of the crank 72 as shown in FIG. 16 (A).

Therefore, in a normal state, the triangular projection 71 of the bevel gear 71
b engages with the leaf spring 71c, which is transmitted to the crank 72 to transmit power.

On the other hand, if an overload is applied to the crank 72 side, FIG.
As described above, the leaf spring 71c is deformed, disengages from the triangular projection 71b of the bevel gear 71, the bevel gear 71 idles, and the transmission of power is cut off.

The significance of providing such a torque limiter is as follows.

First, the bail roller 4 is an area touched by the operator, and the operator touches the bail roller during the automatic opening / closing operation of the bail roller, which may overload the power transmission system.

In addition, when the cassette sheet feeder is mounted on the printer, a part of the cover of the cassette sheet feeder may interfere with the bail shaft and overload the bail roller.

Furthermore, if the control amount for closing the bail roller is too large, the paper is pressed too much, leaving imprints on the copy paper.

For this reason, a torque limiter is provided so that when an overload is applied during the automatic opening / closing of the bail roller, the transmission of power is cut off to prevent the mechanism from being destroyed and imprints on the copy paper to be prevented.

In this embodiment, a torque limiter can be realized with a simple configuration using the leaf spring 71c.

(D) Description of Other Embodiments Although the drive mechanism 7 has been described in each embodiment, the present invention is not limited to this, and the disconnection mechanism 8 is not limited to the embodiment.

Further, the torque limiter may be applied to the second to eighth embodiments, and the tri-limiter is not limited to the ninth embodiment.

Although the present invention has been described with reference to the embodiments, the present invention can be variously modified in accordance with the gist of the present invention, and these are not excluded from the present invention.

〔The invention's effect〕

As described above, according to the present invention, the bail rollers are automatically opened and closed by using the space motor as a drive source, so that the bail rollers can be automatically opened and closed without adversely affecting the sheet loading operation and the like and without providing a dedicated motor. Can be realized, and the automatic opening and closing of the bail roller can be performed stably and inexpensively. Further, since the torque limiter is provided, it is possible to prevent breakage of the mechanism and imprints on the paper.

[Brief description of the drawings]

FIG. 1 is a principle view of the present invention, FIG. 2 is a configuration diagram of a first embodiment of the present invention, FIG. 3 is a sectional view of the first embodiment of the present invention, and FIG. 5 and 6 are explanatory diagrams of the operation of the first embodiment of the present invention, FIG. 7 is a time chart of the first embodiment of the present invention, and FIG. 8 is a second embodiment of the present invention. FIG. 9 is a block diagram of a third embodiment of the present invention, FIG. 10 is a block diagram of a fourth embodiment of the present invention, FIG. 11 is a block diagram of a fifth embodiment of the present invention, FIG. 12 is a block diagram of a sixth embodiment of the present invention, FIG. 13 is a block diagram of a seventh embodiment of the present invention, FIG. 14 is a block diagram of an eighth embodiment of the present invention, FIGS. FIG. 16 is a configuration diagram of a ninth embodiment of the present invention, FIG. 17 is an explanatory diagram of a printer, and FIG. 18 is an explanatory diagram of a prior art. In the drawing, 1 ... print head, 2 ... platen, 4 ... bail roller, 6 ... space motor, 7 ... drive mechanism, 8
…… A disconnection mechanism.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kenji Umehara 1015 Uedanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Limited (72) Inventor Yoshiaki Hosokawa 1015 Kamikodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Fujitsu Limited (72) Inventor Takashi Maekawa 1015 Ueodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Limited (56) References JP-A-63-153170 (JP, A) JP-A-59-76280 (JP, A) Sho-61-19625 (JP, A) Full-scale Sho-62-78447 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B41J 13/00-13/02 B41J 15/04

Claims (1)

(57) [Claims] 1. A platen (2), a print head (1) that moves along the platen (2) and performs printing, and a mover that moves the print head (1) along the platen (2). A space motor (6), and a bail roller (4) for holding a print medium on the platen (2), for driving the bail roller (4) to open and close by the driving force of the space motor (6). A drive mechanism (7); a disconnection mechanism (8) for disconnecting power in the drive mechanism (7); and a torque for disconnecting power transmission when the power transmission in the drive mechanism (7) is overloaded. A bail roller opening / closing mechanism for a printer, which is provided with a limiter.